import java.util.TreeMap;

public class Lianxi56789 {
    public static void main(String[] args) {
        //1.创建集合
        TreeMap treeMap=new TreeMap();

        //2.创建三个学生对象
        Student2 s1 = new Student2("zhangsan", 23);
        Student2 s2 = new Student2("lisi", 21);
        Student2 s3 = new Student2("wangwu", 25);

        //3.添加元素
        treeMap.put(s1, "江苏");
        treeMap.put(s2, "浙江");
        treeMap.put(s3, "福建");
        System.out.println(treeMap);
    }
}
